Is there any "chisaran" (is there something "lacking") in one's fulfillment of the Mitzvah of Talmud Torah if they listen to soft, slow paced, instrumental music (no vocals or lyrics) while learning in order to focus better or drown out background noise?

Let's say a person knows that he can't focus and learn that way. Who says learning aloud takes priority in that case? Or do you propose that such a case does not exist?
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FredJan 14 '13 at 4:29

@Fred If he can't learn aloud, then he must use the best method for him, as you suggest. I know of one academic young man who went to Yeshiva and was given a room to learn in on his own.
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Avrohom YitzchokJan 14 '13 at 9:30

I remember somewhere in RaMbaM that says day time learning in the beith hamadrash is loud due to everyone speaking, arguing, whatever else. But at night it's quiet because people are going to sleep. He then compared the two saying which one is better for which situation you are in. If I find the RaMbaM when I get home, I'll quote it.
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MoriDoweedhYaa3qobMar 11 '13 at 18:22